1. Field of the Invention
This invention relates to a pusher system for a strapping machine. It can shorten the horizontal moving time of the horizontal moving portion. It can shorten the vertical moving time. Plus, it can increase the total processing efficiency.
2. Description of Related Art
Referring to FIGS. 11, 12, 13, 14, and 15, a traditional pusher system for a strapping machine is disclosed. It includes a housing 81, a pair of conveyors 82, and a driving system 83.
About the housing 81, it has a first end 811, a second end 812, and a guiding channel 813. The guiding channel 813 is disposed between the first end 811 and the second end 812.
With regard to the pair of conveyors 82 (or called transport devices), they are disposed on the housing 81. The guiding channel 813 is positioned between the conveyors 82 for allowing a working object 90 (such as a box or a stack to be strapped) to be moved on the conveyors 82 horizontally.
Concerning the driving system 83, it is disposed in the housing 81 and is positioned corresponding to the guiding channel 813. The driving system 83 has a horizontal moving portion 831 and a vertical moving portion 832. The horizontal moving portion 831 is able to move beneath the guiding channel 813 and move between a first position P1 and a second position P2 (see FIG. 16) horizontally. The vertical moving portion 832 is mounted on the horizontal moving portion 831 and can move up or down. The vertical moving portion 832 includes a pusher 83A for pushing the working object 90 moving forward. When it is at an upper position P4, the pusher 83A can protrude in the guiding channel 813 for pushing the working object 90.
As illustrated in FIG. 12, the working object 90 moves in a place on the conveyors 82 via the first end 811 (automatically or manually). Then, the working object 90 is pushed by the pusher 83A to move in a strapping machine 90A via the second end 812 so as to conduct a strapping work.
Referring to FIG. 13, the horizontal moving portion 831 is positioned at the first position P1. The pusher 83A is positioned at the lower position P3. The working object 90 moves on the conveyors 82. The pusher 83A moves up to the upper position P4 (as shown in FIG. 14). Then, the horizontal moving portion 831 moves from the first position P1 to the second position P2 (referring to FIGS. 15 and 16). Initially, the pusher 83A moves certain distance without contacting anything (from FIG. 14 to FIG. 15). Later, the pusher 83A will contact with the working object 90. After which, the pusher 83A continues to push the working object 90 to the strapping machine 90A (see FIG. 16).
As illustrated in FIG. 17, the pusher 83A returns to its lower position P3, and then the horizontal moving portion 831 returns to the first position P1 so that a complete cycle is done.
However, the traditional pusher system for a strapping machine still has many problems and disadvantages as listed below.
[a] The horizontal moving portion only can move back and forth for a fixed distance. The horizontal moving portion only can move between the first position and the second position. It is a fixed stroke (or distance). It cannot be stopped in the middle. For example, if the original design for the horizontal moving portion's moving distance is 1.5 m. The horizontal moving portion only can move forward 1.5 m toward the first end or move back 1.5 m toward the second end.
Therefore, no matter the length of the working object is long or short (such as 30 cm, 100 cm, etc.), the moving distance of 1.5 m is fixed. When the working object is a smaller one, it will cause certain invalid pushing process (that means the pusher does not contact with the working object). It really wastes time. Thus, the horizontal moving distance of the traditional device's horizontal moving portion cannot be adjusted. It is not flexible.
[b] The vertical moving portion only can move up or down for a fixed height. The traditional pusher system only can move up or down between the upper position and the lower position. It cannot stop in the middle. For example, assuming that the original vertical moving distance is designed as 50 cm, the traditional pusher system only can move up 50 cm (directly to the upper position) or move down 50 cm (directly to the lower position).
Under such condition, no matter the working object is larger or smaller (such 25 cm height, 45 cm height, etc.). The vertical moving distance is always fixed as 50 cm. Therefore, when the height of the working object is smaller, the extra moving process (up or down) wastes time. Therefore, the vertical moving distance of the traditional pusher system cannot be adjusted as well.